CN107914080B

CN107914080B - Laser uniform processing device and method thereof

Info

Publication number: CN107914080B
Application number: CN201610989259.2A
Authority: CN
Inventors: 胡平浩; 林茂吉; 林于中; 李闵凯
Original assignee: Industrial Technology Research Institute ITRI
Current assignee: Industrial Technology Research Institute ITRI
Priority date: 2016-10-11
Filing date: 2016-11-10
Publication date: 2020-05-29
Anticipated expiration: 2036-11-10
Also published as: TW201813750A; TWI604907B; US20180101015A1; US10705346B2; CN107914080A

Abstract

The invention discloses a laser uniform processing device and a method thereof. The laser unit provides a laser beam for processing. The shaping element shapes the laser beam into an annular beam. The collimating element corrects the direction of the annular light beam according to the direction of the optical axis so that the annular light beam becomes a collimated annular light beam. The expansion and contraction element adjusts the collimation annular beam according to the multiplying power to generate an expansion and contraction annular beam. The focusing element focuses the expanded and contracted annular light beams into a focused light beam having a uniform distribution of light intensity in the direction of the optical axis.

Description

Laser uniform processing device and method thereof

Technical Field

The present invention relates to a laser processing apparatus and method, and more particularly, to a laser uniform processing apparatus and method.

Background

With the rapid development of touch panel and other industries, the cutting technology of transparent substrates such as tempered glass and sapphire substrates is becoming more and more important. Taking tempered glass as an example, after the surface or the inside of the tempered glass is subjected to a strengthening treatment, a stress of about several tens to several million pascals is generated, so that a conventional processing machine faces a bottleneck in a processing and manufacturing process, and problems such as too fast wear of a processing head or too large processing defects are often caused. Therefore, the laser beam of the laser processing apparatus has characteristics such as high energy density, concentration, and non-contact processing, and thus is widely used in manufacturing processes such as cutting and drilling of a workpiece made of a transparent material.

Fig. 1 is a light intensity distribution diagram of a focused light beam 1 generated by a laser processing apparatus (not shown) in the prior art, and the unit of the vertical coordinate and the horizontal coordinate in fig. 1 can be any unit (a.u).

In the case of an axicon (not shown) as the focusing element of the laser processing apparatus, the central cone angle of the axicon is about 90 degrees to 179 degrees, the light intensity distribution of the focused beam 1 of the axicon in the processing range 11 in the direction of the optical axis is not uniform, and the uniformity of the light intensity distribution is usually less than 50%. Therefore, since the light intensity of the focused light beam 1 is not uniform and has a narrow distribution, it is difficult to define the processing range 11 and the non-processing range 12 of the focused light beam 1, and the focused light beam 1 may not have the same processing characteristics when processing a workpiece, and the cutting speed of the laser processing apparatus is too slow.

In detail, the light intensity of the focused light beam 1 is approximately slightly Gaussian-like distributed in the direction of the optical axis, i.e. the light intensity is strongest at the center of the focused light beam 1 (i.e. the processing range 11), and the upper end and the lower end of the focused light beam 1 (i.e. the non-processing range 12) are gradually attenuated in sequence, and these non-uniform light intensities (energies) cause three disadvantages. The first is that the non-uniform light intensity results in non-uniform cutting ability, such that when the workpiece is cracked or stripped, non-uniform processing features, such as non-uniform roughness, are formed on the cross section of the workpiece, and therefore a more complicated post-processing process is required to solve the non-uniform characteristics of the cross section. Secondly, the light intensity of the focused light beam 1 is too slow in the attenuation speed in the direction of the optical axis, so that the boundary between the processing range 11 and the non-processing range 12 of the focused light beam 1 cannot be clearly defined, and therefore, during the half-cut manufacturing process of the composite workpiece, for example, during the cutting of the upper half of the workpiece, the circuit or glass of the lower half of the workpiece is also damaged, and thus the focused light beam 1 cannot meet the requirement of protecting the lower half of the workpiece in the half-cut manufacturing process. Thirdly, the light intensity of the focused light beam 1 is attenuated too slowly in the direction of the optical axis, so that the light intensity of the focused light beam 1 needs to be distributed to 1.5 times to 2 times of the thickness of the workpiece, and the workpiece is processed by using the strongest energy at the center of the focused light beam 1 (i.e. the processing range 11), but the energy of part of the focused light beam 1 is sacrificed to the non-processing range 12, thereby causing unnecessary energy waste and increasing the construction cost of the laser processing device.

Disclosure of Invention

The invention provides a laser uniform processing device and a method thereof, which can generate a focused light beam with uniformly distributed light intensity.

The laser uniform processing device of the invention comprises: a laser unit, which provides a laser beam for processing; a shaping element for shaping the laser beam provided by the laser unit into an annular beam; a collimating element for correcting the direction of the ring-shaped light beam shaped by the shaping element according to the direction of the optical axis so as to make the ring-shaped light beam become a collimated ring-shaped light beam; a scaling element for adjusting the collimated annular beam generated by the collimating element according to a magnification to generate a scaled annular beam; and a focusing element for focusing the expanded and contracted annular light beam generated by the expansion and contraction element into a focused light beam with uniformly distributed light intensity in the direction of the optical axis.

The laser uniform processing method comprises the following steps: providing a laser beam for processing; shaping the laser beam into an annular beam; correcting the direction of the annular light beam according to the direction of the optical axis so as to enable the annular light beam to become a collimated annular light beam; adjusting the collimated annular light beam according to the magnification to generate a telescopic annular light beam; and focusing the expanded and contracted annular light beam into a focused light beam having a uniform distribution of light intensity in the direction of the optical axis.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below. Additional features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The features and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.

Drawings

FIG. 1 is a graph of a light intensity profile of a focused beam of light produced by a prior art laser processing apparatus;

FIG. 2 is a block diagram of a laser leveling apparatus according to the present invention;

FIG. 3 is a flow chart of the steps of the laser uniform machining method of the present invention;

FIG. 4A is a light intensity distribution diagram of the laser beam provided by the laser unit at line A1 in the laser leveling apparatus of FIG. 2 according to the present invention;

FIG. 4B is a diagram illustrating a distribution of light intensity of the ring-shaped light beam generated by the shaping device at line A2 in the laser leveling device of FIG. 2 according to the present invention;

FIG. 4B' is a graph of the light intensity distribution of the ring beam on the enlarged right side of FIG. 4B according to the present invention;

FIG. 4C is a light intensity distribution diagram of the collimated annular light beam generated by the collimating element at line A3 in the laser uniform processing apparatus of FIG. 2 according to the present invention;

FIG. 4D is a diagram illustrating a light intensity distribution of the expanded annular beam generated by the expanding and contracting element at line A4 in the laser leveling apparatus of FIG. 2 according to the present invention;

FIG. 4E is a diagram illustrating a light intensity distribution of a focused light beam generated by a focusing device in the laser micromachining apparatus of FIG. 2 according to the present invention; and

fig. 4E' and 4E ″ are light intensity distribution diagrams of the focused light beam generated by the expanding and contracting element with different magnifications in the laser uniform processing device of fig. 2 according to the present invention.

Description of the symbols

1 focused light beam

11 machining Range

12 non-working range

2 laser uniform processing device

21 laser unit

211 laser beam

22 shaping element

221 annular light beam

23 collimating element

231 collimating annular light beam

24a,24b expansion and contraction element

241 expanding and contracting annular light beam

25 focusing element

251 focused light beam

Segment A1, segment A2, segment A3 and segment A4

B. B ', B' processing scope

C. Non-processing range of C' and C

L optical axis

N adjustable integer value

R radial coordinate

r_oConstant number

Width of W ring

W₀Diameter of

S31 to S35.

Detailed Description

The present invention is described in terms of specific embodiments, and other advantages and benefits of the present invention will become apparent to those skilled in the art from the description herein, and may be implemented or applied in other different embodiments.

Fig. 2 is a block diagram of the laser uniform processing apparatus 2 according to the present invention. Fig. 3 is a flowchart of the steps of the laser uniform processing method of the present invention. Fig. 4A is a light intensity distribution diagram of the laser beam 211 provided by the laser unit 21 in the laser uniform processing apparatus 2 of fig. 2 at line a1 according to the present invention. FIG. 4B is a light intensity distribution diagram of the ring beam 221 generated by the shaping device 22 at line A2 in the laser leveling apparatus 2 of FIG. 2 according to the present invention. FIG. 4B' is a diagram illustrating the light intensity distribution of the ring beam 221 on the enlarged right side of FIG. 4B according to the present invention. Fig. 4C is a light intensity distribution diagram of the collimated annular light beam 231 generated by the collimating element 23 in the laser uniform processing device 2 of fig. 2 at the line segment a3 according to the present invention. FIG. 4D is a light intensity distribution diagram of the expanded annular light beam 241 generated by the expanding and

contracting elements

24a,24b in the laser homogenizing apparatus 2 of FIG. 2 according to the present invention at line segment A4. Fig. 4E is a light intensity distribution diagram of the focused light beam 251 generated by the focusing device 25 in the laser uniform processing apparatus 2 of fig. 2 according to the present invention.

In the present invention, the unit of the vertical coordinate and the horizontal coordinate in fig. 4A to 4E ″ may be any unit (a.u), that is, a unit without limitation.

As shown in fig. 2, the laser uniform processing apparatus 2 may include: a laser unit 21, an integer element 22, a collimation element 23, a contraction and

expansion element

24a,24b, and a focusing element 25, which are arranged or corresponding to each other in sequence, but not limited thereto. In other embodiments, the laser homogenizing apparatus 2 can also include other elements (e.g., optical elements) before, after, or between any adjacent two of the laser units 21 to the focusing element 25.

The laser unit 21 provides a laser beam 211 for machining as shown in fig. 4A. The laser unit 21 may be a laser generator, and the laser beam 211 may be a gaussian beam, but not limited thereto.

The shaping element 22 shapes the laser beam 211 provided by the laser unit 21 into an annular beam 221 as shown in fig. 4B (fig. 4B') or at least a light pattern with a ring-shaped distribution. The shaping element 22 can be a phase modulation element, an amplitude modulation element, a diffraction element, an aspheric element, a spherical element, an absorption filter, or a reflection filter.

The collimating element 23 modifies the direction of the annular light beam 221 shaped by the shaping element 22 according to the direction of the optical axis L, so that the annular light beam 221 becomes a collimated annular light beam 231 (i.e. a collimated or modified annular light beam) as shown in fig. 4C. For example, the collimating element 23 can reduce the divergence angle of the annular beam 221 of FIG. 4B (FIG. 4B') to within 10 degrees to produce the collimated annular beam 231 of FIG. 4C. The collimating element 23 can be a phase modulating element, a diffractive element, an aspheric element, or a spherical element.

The expansion and

contraction elements

24a,24b adjust the collimated annular beam 231 generated by the collimating element 23 according to the magnification to generate an expanded annular beam 241 (i.e. an expanded or adjusted annular beam) as shown in fig. 4D. For example, the enlarging and reducing elements 24a,24B can enlarge or reduce the collimated annular beam 231 of fig. 4C to the enlarged and reduced annular beam 241 of fig. 4D according to an adjustable magnification or a fixed magnification, so that the enlarged and reduced annular beam 241 becomes a focused beam 251 (see fig. 4E) with an adjustable processing range B or processing depth after passing through the focusing element 25.

The focusing element 25 focuses the expanded and contracted annular light beams 241 generated by the expanding and

contracting elements

24a,24b into a focused light beam 251 as shown in fig. 4E, and the focused light beam 251 has a uniform distribution of light intensity in the direction of the optical axis L. The focusing element 25 can be an axicon, a diffractive element, a spherical mirror or an aspherical mirror, etc., and the focused beam 251 can be a Bessel (Bessel) beam, etc.

As shown in fig. 3 and fig. 4A to 4E ", referring to fig. 2, the steps of the laser uniform processing method of the present invention are as follows:

in step S31, a laser beam 211 for processing as shown in fig. 4A is supplied from the laser unit 21.

In step S32, the laser beam 211 provided by the laser unit 21 is shaped by the shaping element 22 into an annular beam 221 as shown in fig. 4B (fig. 4B') or at least a light pattern with an annular distribution.

The shaping device 22 can adjust the light intensity distribution of the annular light beam 221 according to the relationship between the light intensity I of the annular light beam 221 and the radial coordinate R as shown in the following equation (1):

I(R)＝I_o·(R-r_o)^-N·D(R,W,W_o)......(1)

where I is the light intensity of the annular light beam 211. R is the radial coordinate of the annular beam 211. I is_oAnd r_oAre all constants. N is an adjustable value and has a value in one of the ranges of 0.1 to 5, such as 0.1, 1, 2, or 5. W and W_oThe ring width and diameter of the ring beam 211, respectively. (R-R)_o)^-NFor determining the intensity I of the annular light beam 211 relative to a constant r_oSpeed of decay, therefore (R-R)_o)^-NCan be regarded as an envelope function of the annular light beam 211, i.e. an attenuation function of the light intensity envelope from the inner edge to the outer edge of the annular light beam 211.

Furthermore, D (R, W)_o) Is a function of the ring width of the ring beam 211, and is mainly used to determine the ring width W and the diameter W of the ring beam 211_oAnd the like. With a ring width W and a diameter W_oFor the example of the ring beam 211, the halo width function D (R, W)_o) The values of (A) are as follows:

when the shaping element 22 shapes the annular light beam 211 into the annular light beam 211, the phase of the annular light beam 211 is affected, so that the aberration of the annular light beam 211 is increased, and the diffusion angle of the annular light beam 211 is increased, so that after the annular light beam 211 propagates for a certain distance, the light shape of the annular light beam 211 is not changed to generate an irregular light intensity distribution, thereby affecting the uniformity of the subsequently generated focused light beam 251, such as a bessel beam.

In step S33, in order to solve the problem of the aberration increase and the divergence angle increase of the annular light beam 211, the aberration of the annular light beam 221 is reduced by the collimating element 23, and the direction of the annular light beam 221 shaped by the shaping element 22 is modified according to the direction of the optical axis L, for example, the divergence angle of the annular light beam 221 is reduced to within 10 degrees, so that the annular light beam 221 becomes a collimated annular light beam 231 (i.e. a collimated or modified annular light beam) as shown in fig. 4C, so as to prevent the propagation mode of the annular light beam 211 from being changed, and further avoid affecting the uniformity of the subsequently generated focused light beam 251 (see fig. 4E). Meanwhile, the small diffusion angle of the ring beam 221 means that a small volume of optical elements can be used, which contributes to the cost of the laser uniform machining apparatus 2.

In step S34, the collimating annular beam 231 generated by the collimating element 23 is adjusted by the expanding and

contracting elements

24a,24b according to the magnification to generate an expanded and contracted annular beam 241 (i.e. an expanded and contracted or adjusted annular beam) as shown in fig. 4D. For example, the expansion/

contraction elements

24a,24b can expand or contract the collimated annular beam 231 into an expanded annular beam 241 according to an adjustable or fixed magnification, i.e. a scaled-up or scaled-down expanded annular beam 241, and the ring width W and diameter W of the expanded annular beam 241_oAre modulated by the magnification ratio of the expansion and

contraction elements

24a,24 b. Thus, the expanded and contracted annular light beam 241 is made to pass through the focusing element 25 to become a focused light beam 251 with adjustable processing range or processing depth of field of the processed workpiece. The adjustable or fixed magnification of the expansion and

contraction elements

24a,24b may be one of a range of 0.1 to 10, such as 0.1, 0.5, 1, 2 or 10.

In step S35, the expanded and contracted annular light beams 241 generated by the expansion and

contraction elements

24a,24b are focused by the focusing element 25 into a focused light beam 251 as shown in fig. 4E, and the focused light beam 251 has a uniform distribution of light intensity in the direction of the optical axis L.

Specifically, when the envelope function (R-R) of the annular light beam 211 is shown in FIG. 4B (FIG. 4B') above_o)^-NWhen the adjustable value N is one of the ranges of 0.1 to 5, the focused light beam 251 in fig. 4E may have a uniform distribution or a flat-top distribution (see the processing range B) of light intensity in the direction of the optical axis L, and the uniformity of the light intensity of the focused light beam 251 is greater than 70%, which is different from the prior art in which the light intensity of the focused light beam 1 in fig. 1 is not uniform and the uniformity of the light intensity of the focused light beam 1 is less than 50%.

Fig. 4E' and 4E ″ are light intensity distribution diagrams of the focused light beams 251 generated by the

scaling elements

24a and 24b with different magnifications in the laser uniform processing apparatus 2 of fig. 2 according to the present invention.

As shown, when the magnification of the expanding and

contracting elements

24a,24b of FIG. 2 is changed, the ring width W and the diameter W of the expanded beam 241_oWill be changed in size. The change in the ring width W of the expanded beam annular beam 241 affects the working spacing (i.e., working distance) of the focused beam 251, while the diameter W of the expanded beam annular beam 241_oWill change the process range B or process depth of field of the focused beam 251. Therefore, when the magnification of the enlarging and reducing elements 24a,24B is enlarged or reduced, the ring width W of the expanded annular beam 241 is changed by a certain magnification, thereby effectively modulating the focused beam 251 into the processing range B '(the enlargement ratio is about 1) as shown in fig. 4E', or into the processing range B '(the enlargement ratio is about 2) as shown in fig. 4E ″, and modulating the non-processing ranges C' and C 'as shown in fig. 4E' and 4E ″.

Therefore, as shown in fig. 4E, 4E 'or 4E ″, the present invention forms a focused light beam 251 having a uniform distribution or flat-top distribution (see the processing range B, B' or B ") of light intensity in the direction of the optical axis L, so that the focused light beam 251 can generate a uniform intensity distribution over the thickness of a workpiece when the workpiece is processed, thereby forming better processing quality. Meanwhile, in the direction of the optical axis L, the attenuation speed of the energy at the end (e.g., the non-processing range C) of the focused beam 251 of the present invention is faster than the attenuation speed of the energy at the end (e.g., the non-processing range 12) of the focused beam 1 of the prior art fig. 1, so as to more clearly define the processing range B (B 'or B ") and the non-processing range C (C' or C") as shown in fig. 2 (fig. 4E to 4E "), thereby solving the problem that the laser uniform processing apparatus of the prior art is not suitable for the half-cut manufacturing process.

In addition, as shown in fig. 4D and 4E, when the intensity of the edge of the expanded beam annular light beam 241 is rapidly attenuated to zero, a slight oscillation condition is brought to the uniform distribution (flat-top distribution) of the light intensity of the focused light beam 251, and to solve the oscillation condition, the expanded beam annular light beam 241 can be rapidly attenuated to zero in a soft manner (see fig. 4E' or fig. 4E "). Therefore, the shaping device 22 can adjust the light intensity distribution of the expanded annular light beam 241 according to the relationship between the radial coordinate R and the light intensity I of the annular light beam 211 shown in the following modified expression (2):

I(R)＝I_o·(R-r_o)^-N.D(R,W,W_o)+S(R,W,W_o)......(2)

wherein S (R) is a smoothing function for smoothly adjusting the attenuation speed of the edge of the ring-shaped light beam 211.

Therefore, by properly adjusting the smoothing function s (r), the uniformity of the light intensity of the focused light beam 251 in the direction of the optical axis L can be improved, and generally the uniformity of the light intensity of the focused light beam 251 can be improved from 70% to over 90%. Basically, the smoothing function s (r) is only used to determine the attenuation speed at the edge of the ring beam 221, and has less influence on the envelope intensity.

As can be seen from the above, in the laser uniform processing apparatus and the method thereof of the present invention, the processing range of the focused light beam in the direction of the optical axis can be adjusted (enlarged or reduced), and the uniformity of the light intensity distribution of the focused light beam is improved, thereby achieving the uniformity of the processing result of the workpiece, also improving the processing speed of the workpiece, and being suitable for the half-cut manufacturing process of the composite workpiece, further reducing the unnecessary energy waste, and also reducing the construction cost of the laser processing apparatus.

The above-described embodiments are merely illustrative of the principles, features and effects of the present invention, and are not intended to limit the scope of the invention, which can be modified and varied by those skilled in the art without departing from the spirit and scope of the invention. Any equivalent changes and modifications made by the present disclosure should be covered by the scope of the claims. Therefore, the scope of the invention should be determined from the following claims.

Claims

1. A laser uniform processing apparatus, characterized by comprising:

a laser unit which provides a laser beam for processing;

a shaping element for shaping the laser beam provided by the laser unit into an annular beam;

the collimating element corrects the direction of the annular beam shaped by the shaping element according to the direction of the optical axis so as to enable the annular beam to become a collimated annular beam;

a scaling element for adjusting the collimated annular beam generated by the collimating element according to a magnification to generate a scaled annular beam; and

a focusing element that focuses the expanded and contracted annular light beam generated by the expanding and contracting element into a single focused light beam having a uniform distribution of light intensity in the direction of the optical axis;

the laser beam is adjusted into the annular beam, the collimating annular beam, the expanding annular beam and the single focusing beam with uniformly distributed light intensity in sequence by the laser uniform processing device, the shaping element is positioned between the laser unit and the collimating element, and the expanding element is positioned between the collimating element and the focusing element.

2. The laser uniform processing apparatus of claim 1, wherein the laser beam is a gaussian beam and the focused beam is a Bessel beam.

3. The laser beam uniformity processing apparatus of claim 1, wherein the shaping element is a phase modulation element, an amplitude modulation element, a diffraction element, an aspheric element, a spherical element, an absorption filter, or a reflection filter.

4. The laser uniform processing apparatus of claim 1, wherein the shaping element adjusts the light intensity distribution of the annular beam according to the relationship between the light intensity and the radial coordinate of the annular beam expressed by the following operational formula:

I(R)＝I_o·(R-r_o)^-N·D(R,W,W_o)

wherein I is the light intensity of the annular light beam, R is the radial coordinate of the annular light beam, I_oAnd r_oAre all constants, N is an adjustable integer value, W and W_oThe ring width and diameter (R-R) of the ring beam_o)^-NAs a function of the envelope of the annular beam, D (R, W)_o) As a function of the halo width of the ring beam.

5. The apparatus of claim 4, wherein the shaping element adjusts the light intensity distribution of the annular beam according to the relationship between the light intensity and radial coordinate of the annular beam as shown in the following modified arithmetic expression:

I(R)＝I_o·(R-r_o)^-N·D(R,W,W_o)+S(R,W,W_o)

wherein S (R) is a smoothing function for smoothly adjusting the attenuation speed of the edge of the focused light beam.

6. The laser uniform processing apparatus of claim 1, wherein the collimating element is a phase modulating element, a diffractive element, an aspheric element or a spherical element.

7. The laser uniform processing apparatus of claim 1, wherein the collimating element reduces a divergence angle of the annular beam shaped by the shaping element to within 10 degrees to produce the collimated annular beam.

8. The apparatus of claim 1, wherein the expanding and contracting element expands or contracts the collimated annular beam into the expanded and contracted annular beam according to an adjustable magnification or a fixed magnification, so that the expanded and contracted annular beam becomes the focused beam with an adjustable processing range or processing depth after passing through the focusing element.

9. The laser leveling apparatus of claim 1 wherein the focusing element is an axicon.

10. The laser leveling apparatus of claim 1 wherein the focusing element is a diffractive element, a spherical mirror or an aspherical mirror.

11. The laser leveling apparatus of claim 1 wherein the light intensity of the focused beam is uniformly distributed or flat-topped and the uniformity of the light intensity of the focused beam is greater than 70%.

12. A laser uniform processing method, characterized in that the method comprises:

providing a laser beam for processing;

shaping the laser beam into an annular beam;

correcting the direction of the annular light beam according to the direction of the optical axis so as to enable the annular light beam to become a collimated annular light beam;

adjusting the collimated annular light beam according to the magnification to generate a telescopic annular light beam; and

focusing the expanded and contracted annular light beams into a single focused light beam having a uniform distribution of light intensity in the direction of the optical axis;

the laser beam is adjusted into the annular beam, the collimating annular beam, the expanding annular beam and the single focusing beam with uniformly distributed light intensity in sequence by the laser uniform processing method.

13. The laser machining method of claim 12, wherein the laser beam is a gaussian beam and the focused beam is a bessel beam.

14. The laser uniform processing method of claim 12, wherein the light intensity distribution of the annular beam is adjusted according to the relationship between the light intensity of the annular beam and the radial coordinate as shown in the following operational formula:

I(R)＝I_o·(R-r_o)^-N·D(R,W,W_o)

15. The laser uniform processing method of claim 14, wherein the light intensity distribution of the annular beam is adjusted according to the relationship between the light intensity and radial coordinate of the annular beam as shown in the following modified operational formula:

I(R)＝I_o·(R-r_o)^-N·D(R,W,W_o)+S(R,W,W_o)

16. The laser micromachining process of claim 14 wherein said adjustable value N is one of a value in the range of 0.1 to 5.

17. The laser uniformity processing method of claim 12, wherein the divergence angle of the annular beam is reduced to within 10 degrees to produce the collimated annular beam.

18. The laser uniformity processing method of claim 12, wherein aberrations of the annular beam are reduced to produce the collimated annular beam.

19. The laser uniform processing method of claim 12, wherein the collimated annular beam is enlarged or reduced to the enlarged annular beam according to an adjustable or fixed magnification, so that the enlarged annular beam is followed by the focused beam with adjustable processing range or processing depth.

20. The laser leveling method of claim 19 wherein the adjustable magnification or the fixed magnification is one of in the range of 0.1 to 10 times.

21. The laser leveling method of claim 12 wherein the light intensity of the focused beam is uniformly distributed or flat-top distributed and the uniformity of the light intensity of the focused beam is greater than 70%.